Oh, wow, really? I always assumed access points were considered unique things, the SSID being just somthing for humans to more easily identify them....

Corporates will have dozens of APs all broadcasting the same SSID, and you wouldn't want to separately have to configure connecting to each one, so yes, most (all?) mobile devices treat the same SSID as the same network even on different APs.

I see; i hadn't put much thought into it, i was assuming there was some other detail that would get into play when dealing with such corporate networks. What happens when more than one access point is in range that has the same SSID though?

It will probably connect to the one with the strongest signal, I guess.

If they're on the same channel, can your phone get confused? I currently use 2 access points at home to cover the area well - ok, to cover the flat + enough down the road that I can carry on checking for tube/train delays on the way out in the morning if I left it til last minute.

I tried them on the same SSID once, with same WPA2 password, but things got confused and they both were prone to stop working. With unique SSID's(albeit similar) they're much more stable. Is this 'cos they're only consumer routers and not tested for this eventuality so much, or are there inherantly issues doing this? I should prob be checking this out on a wifi networking geeky forum not here, but the subject's come up..

Back on track - I'd also love a way to stop it auto-adding certain access points, I'm a Fonero (fon.com) and share my wifi/am able to use other fon AP's around that share. Too many of them are broken though, and I hate when it picks up to these broken ones even if I'm connected via 3G and working on it. I'd miss autoconnecting back to my own wifi when I got home if I turned it off and it'd be a tougher habit to get back into specially when Im tired in the evening, my 3G data plan isn't unlimited enough to not care.

Could I write something to do the job with filtering on (by MAC maybe?) to ignore broken APs - and then turn off the builtin thing that does the same? Im sure I could, given time; its just how complicated it would be. Dbus service stuff involved, I might guess..

Feature suggestion: in the list of saved access-points, what about a flag to say "this is saved so I know not to use it" AP? Asking for specific device filtering is more complicated (at least UI and code wise) rather than by SSID though and would probably still involve disconnecting from any current AP temporarily to check out the new one.

This should work if they are physically two access points.
All data adressing / negotiation is done by using the mac address, not the ssid. Things get fishy when you assign them the same channel AND mac address, but nobody would actually do that. Once your WPA2 connection is established, only the AP you are actually connected with can listen to your connection, even if the other one has the same password.

WPA2 utilizes sessions.

Advice: Don't do that, if both APs are in range of each other. You will get slower connection speeds or packet drops.

How about somthing that will not pay attention to SSIDs, but only to MAC addresses, and will keep a black and a whitelist of MACs to automaticly connect to (with a way for deleting entries on the lists as well as moving from one list to another), the entries being created just before connecting to a never seen before MAC address, with a dialog asking whether you want to autoconect in the future or not or if you want to be asked again next time ?